Falling right into line with the Galaxy Nexus devices receiving an OTA, the Wi-Fi Motorola Xoom seems to be getting a 4.1.2 Jelly Bean update as well. Users in our forums are starting to report that their devices are pulling down the update and although these updates are usually on a staggered rollout, we would expect it to start showing up on all devices shortly.
We've seen the official 4.1.2 Jelly Bean changelog at this point -- with most improvements coming to the Nexus 7 -- but have yet to receive an official update page from Motorola. It will likely be put up once the OTA is a bit more widespread. If you're antsy, you can grab a direct download of the OTA file at the second source link. Before flashing, why not check out the forums and make sure you've got all the tips and tools you need.